对病毒性心肌炎疗效最好的为
A．人参B．党参C．黄芪D．甘草E．白术
参考答案：C
如图所示，AB棒与BC棒用光滑的饺链铰在B点，A、C也用光滑的饺链铰于墙上．BC棒水平，AB棒与竖直成45°角，两棒等长等重．则两捧在B点的相互作用力的方向：
(A)可能与AB棒平行. (B)可能与BC棒平行.
(C)可能与虚线DE平行. (D)可能与虚线FG平行.
We thought it was he who did it, but it _________ that he wasn’t even there.
A．turned up
B．turned down
C．turned off
D．turned out
